Gardner Denver EDF-KB, Руководство по эксплуатации и обслуживанию

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13–8–606 Page 24
FIGURE 4–5 – PRESSURE CHART
Moisture, oil and dirt in the control system lines and
components can cause the set point of the subtractive
pilot to shift or be erratic. The subtractive pilot can be
disassembled and the diaphragm and ports cleaned
when necessary.
Operating Air Pressure Adjustment – The Auto–
Sentry S controller load and unload pressure setpoints
should already be programmed. See page 21, and
FIGURE 4–8, page 25.
Operation at excessive discharge air
pressure can cause personal injury or
damage to equipment. Do not set un-
load pressure above the maximum
stamped on the unit nameplate.
To adjust the subtractive pilot:
1. With the unit off, loosen the locknut and back out
the adjusting screw several turns so the subtrac-
tive pilot will fully unload the compressor before
the unload pressure setpoint of the microproces-
sor controller is reached.
2. Close the air service valve and start the unit in
the “CONSTANT RUN” mode. Allow the unit to
reach the pressure at which the subtractive pilot
fully unloads the compressor.
3. Turn–in the adjusting screw until the unload
pressure setpoint is reached and the micropro-
cessor controller allows the unit to blow down.
4. Turn–in the adjusting screw an additional one–
eighth (1/8) turn and tighten the locknut. As a re-
sult, the subtractive pilot will not fully unload the
compressor before the microprocessor control-
ler’s unload pressure setpoint is reached.
5. Using the air service valve, cycle the unit be-
tween load and unload several times to be cer-
tain that the unit will reach the microprocessor
controller’s unload pressure setpoint and blow
down.
FIGURE 4–6 – SUBTRACTIVE PILOT (CLOSED) FIGURE 4–7 – SUBTRACTIVE PILOT (OPENED)